1. Field of the Invention
This invention relates to the dislodging or loosening of mucus in a person's lungs.
Cystic fibrosis is an inherited disease which damages vital organs, especially the lungs and pancreas, by clogging them with mucus. Drugs exist which can ameliorate its effects, but physical management of the disease is nevertheless very important.
Mucus is continually produced in the lungs and keeps the airways moist. Particles of dust, dirt or bacteria lodge in the mucus, which is cleared in the healthy lung and swallowed. This process happens all the time and is the way that the lungs keep themselves clear and free of infection.
The mucus produced by cystic fibrosis sufferers contains less water than it should and hence is sticky. As a result, the process of cleaning of the lungs is inefficient or absent leading to build-up of bacteria, dirt and mucus in the lungs. Infection as a result is more likely.
2. Description of the Prior Art
Current physical management relies on using motion of the lungs to dislodge mucus. This can be induced by controlled breathing, and by shaking or clapping of the front, back and/or sides of the chest with the hands. The mechanism by which motion causes clearing of the lungs is not completely understood, but it is probable that it is at least partly because mucus is a thixotropic fluid, that is, one which becomes more fluid when vibrated.
Physical movement of the chest by means of clapping or shaking is likely to be a very inefficient way of causing vibration of the lungs, since the chest wall will resist movement. It is labour intensive and usually requires a partner to administer. In addition, it has to be carefully taught and practised, since the possibility exists of injury if administered too forcefully. This is particularly important in young children and babies who may be unable to give any indication as to its acceptability.